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<script>
    var str = "！我是---，年龄是18  记得我哦";
    var arr = [];
    console.log(str);
    console.log(arr);
    for (var i = 0; i < str.length; i++) {
        arr.push(str.substr(i, 1));
    }
    console.log(arr);


    var str = "A23423412";
    console.log(/[A-Za-z]/.test(str))
    if(/[A-Za-z]/.test(str)){
        console.log("存在大写或小写字母")
    }else{
        console.log("不存在大写或小写字母")
    }
   
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